Castle Serenity Exhaust Settings

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Dec 8, 2021
Napa, California
Hey everybody,

We have a Castle Serenity stove, installed with a DuraVent Gray 3-in pellet vent kit. No outside air intake (the cabin is not air-tight, and there's plenty of drafts/ventilation). We're in a high fire risk area, and I need some help getting these settings correct. This forum has been super helpful getting us to this point!

After installation, we noticed a LOT of sparks flying out the vent. After searching this forum, I've made adjustments to the exhaust and blower speeds to reduce the amount of sparks we're seeing. This seems to have worked (we only see an occasional spark at the higher fan settings) and has resulted in much more heat staying in the cabin. The only issue is that we're getting a bit of a lazy flame and black soot on the window when running on the higher fan settings. I reached out to Castle who responded with some baffling information, and I'm wondering what everyone here thinks.

My current settings are:

Blower Voltage:

1. 95V
2, 105V
3. 110V
4. 115V
5. 115V

Exhaust Voltage

1. 80V
2. 85V
3. 85V
4. 90V
5. 90V

Castle responded with this:

"The exhaust is too low so it is not pulling enough air in over the firepot. The voltages are set two far apart. There must be 10 volt difference or less and staggered."

They recommended these settings (which in my case seems like it will definitely blow sparks and most of the heat out the vent).

80, 85, 90, 95, 100, 110

90, 95, 100, 105, 115

I'm curious to hear what y'all think. Have you ever heard of the "10 volt difference" requirement? Is there another way I can fix the black soot issue?

Thanks in advance!

You are not putting enough air into the fire for a clean burn
Dirty burn (Lazey flame ) = dirty black glass
As far as your voltage settings can't help you there.